A steering controller is known that recognizes the shape (such as the curvature) of a road along which a vehicle is driving on the basis of a captured image of a view ahead of the vehicle, calculates the drift and the deflection angle of the vehicle with respect to the shape of the road that is recognized, and controls steering of the vehicle on the basis of the drift and the deflection angle (see, for example, Japanese Unexamined Patent Application Publication No. 2006-15996).
It is required that the steering controller described in Japanese Unexamined Patent Application Publication No. 2006-15996 more appropriately recognize the shape of a road when the vehicle is driving along a road whose shape changes considerably, such as a transitional section between a curved road section and a linear road section, so that the steering controller can appropriately control steering of the vehicle. In particular, it is required that the steering controller more appropriately recognize the shape of a road when the vehicle is driving along a road that suddenly changes from a curved road section to a linear road section and vice versa (that is, a road whose curvature suddenly changes).